Ghuzlan Alghazali, 26, was arrested overnight and accused of two counts of motor vehicle homicide, one count of negligent operation of a motor vehicle and one count of unlicensed operation of a motor vehicle, the Suffolk County district attorney said.

She was scheduled to be arraigned Tuesday in Boston Municipal Court, but prosecutors then said they needed more time to sort out evidence on who was driving the car.

Kennedy is an emergency room nurse. She heard a loud "bang" Saturday night at the intersection of Beacon and Fairfield streets.

"I ran around to the back of the car, and that's when I saw the pedestrians," she said. "They were pinned, and they weren't moving, unfortunately."

Lanzillotti was already dead, Kennedy said, but she had hope that Campbell might survive.

"I knelt down, held her hand because I wasn't sure how alert she was at the time -- her eyes were open -- and I just said, 'Help is coming. Stay with me. Stay with me,'" Kennedy recounted from the scene of crash.

"In all my years in emergency and acute care, I felt helpless. There was nothing I could do."

Campbell was transported to Brigham and Women's Hospital, where she was later pronounced dead.Kennedy left that note Monday, hoping it would help ease the minds of the couple's parents.

"As a parent, I wanted their parents to know that I was there, that I was talking to them," she said.

Friends and family of the victims tell NewsCenter 5 that Lanzillotti and Campbell, who had been dating for two years and had just moved in together into a Brookline apartment, were walking home 9 p.m. Saturday from an evening on the Esplanade.

A black SUV, witnesses said, blew a red light on Beacon Street, smashed into a sedan, and then rolled on top of Lanzillotti and Campbell.

Kennedy said people speed and run reds far too often on Beacon Street, noting there have been three serious accidents in the past few years at the Beacon-Fairfield intersection.

"We have to slow down. We have to pay attention," she said. "I certainly would never, ever want anyone to experience this again."

Photos: 2 dead, others hurt in Back Bay crash

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Two pedestrians were killed and two others were hurt Saturday night in a multi-vehicle crash on Beacon Street in the Back Bay.

WHAT THE SHARK DID THAT SURPRISED EVERYONE. ONLY ON 5, ONE OF THE SUSPECTS IN A DEADLY CRASH CONFRONTED BY NEWSCENTER 5. HIS WIFE RELEASED FROM CUSTODY AS THEY TAKE A DEEPER LOOK AT THIS CASE. NEWSCENTER 5'S JULIE IS THEIR LIFE. THE HUSBAND AND WIFE WERE ARRESTED. BOTH WERE RELEASED WITHOUT ANY CHARGES. THEIR ATTORNEYS TELL ME THAT THEY HAVE BEEN NOTHING BUT A WHOPPER TO OF. THEY ARE WANTED IN CONNECTION WITH THE CRASH THAT KILLED TWO PEOPLE ARE NOW BEING -- NOT BEING CHARGED. DO YOU WANT TO SAY ANYTHING ABOUT WHAT HAPPENED SATURDAY NIGHT? WHO WAS DRIVING? HIS WIFE SPENT THE DAY WAITING TO BE ARRAIGNED. THE DISTRICT ATTORNEY'S OFFICE SAID THAT THEY NEEDED MORE TIME. THEY ASSURED THE FAMILIES THAT EVERY STEP THAT THEY TAKE IN THIS PROBE IS WITH THE INTENTION OF SEEING JUSTICE DONE FOR THEM AND THEIR LOVED ONES. THEY ARE DEEPLY RELIGIOUS PEOPLE AND VERY SADDENED. THE 26-YEAR-OLD MOTHER OF FOUR IS A CITIZEN OF YEMEN AND A GREEN CARD HOLDER. SHE DOES NOT HAVE A DRIVERS LICENSE. IT IS A TERRIBLE TRAGEDY. THAT IS WHAT IT IS AT THIS POINT. THE BLACK SUV RAN A RED LIGHT BEFORE BEING HIT BY A CAR, FLIPPED OVER, AND LANDED ON A COUPLE ON THE SIDEWALK. THEY ARE JUST BESIDE THEMSELVES WITH GRIEF. THEY ARE

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